Voyager 1 Entering Interstellar Space
June 15, 2012

Voyager 1 Entering Interstellar Space

Lee Rannals for

After several decades of making a lonely journey across our solar system, Voyager 1 has signaled to NASA that it may have reached the edge of interstellar space.

The spacecraft, which launched in 1977, is now roughly 11 billion miles away and traveling at 6 miles per second.

NASA said it takes Voyager 1's data 16 hours and 38 minutes to reach the antennas of its Deep Space Network on Earth.

Data from the spacecraft indicates that the 34-year-old man-made object has encountered a region in space where the intensity of charged particles from beyond our solar system has markedly increased.

"The laws of physics say that someday Voyager will become the first human-made object to enter interstellar space, but we still do not know exactly when that someday will be," Ed Stone, Voyager project scientist at the California Institute of Technology in Pasadena, said in a press release. "The latest data indicate that we are clearly in a new region where things are changing more quickly. It is very exciting. We are approaching the solar system's frontier."

The data received by NASA detail the number of charged particles measured by the two High Energy telescopes aboard the spacecraft. NASA said these energetic particles were generated when neighboring stars went supernova.

"From January 2009 to January 2012, there had been a gradual increase of about 25 percent in the amount of galactic cosmic rays Voyager was encountering," Stone said in the release. "More recently, we have seen very rapid escalation in that part of the energy spectrum. Beginning on May 7, the cosmic ray hits have increased five percent in a week and nine percent in a month."

According to NASA, this increase is one of three data sets needed to ensure man's machine is entering a new era in space travel. The second measure from the spacecraft's two telescopes is intensity of energetic particles generated inside the heliosphere, which is the bubble of charged particles the sun blows around itself.

The space agency said the final data set Voyager scientists need to reveal a change is the measurement in the direction of the magnetic field lines surrounding the spacecraft. When Voyager 1 breaches into interstellar space, the team believes it will find that the spacecraft's magnetic field lines orient in a north-south direction, as opposed to its current east-west configuration.

"When the Voyagers launched in 1977, the space age was all of 20 years old," Stone continued in the release. "Many of us on the team dreamed of reaching interstellar space, but we really had no way of knowing how long a journey it would be -- or if these two vehicles that we invested so much time and energy in would operate long enough to reach it."

Voyager 1's brother spacecraft, Voyager 2, is more than 9.1 billion miles away from the Sun. The spacecraft are the two most distant human-made objects exploring.

Image 2 (below): This artist's concept shows NASA's two Voyager spacecraft exploring a turbulent region of space known as the heliosheath, the outer shell of the bubble of charged particles around our sun. Image credit: NASA/JPL-Caltech